Abstract:

A fuel cell stack including a first end plate, a second end plate, at
least a fuel cell, a first current collector and a second current
collector is provided. The first end plate includes a first end plate
structure component, which is combined with a first end plate manifold
component. The second end plate includes a second end plate structure
component, which is combined with a second end plate manifold component.
The first and the second end plate manifold components are placed between
the first and the second end plate structure components, while the fuel
cell is disposed between the first and the second end plate manifold
components. The first current collector is disposed between the first end
plate manifold component and the fuel cell. The second current collector
is disposed between the second end plate manifold component and the fuel
cell.

Claims:

1. A fuel cell stack, comprising:a first end plate, comprising:a first end
plate structure component; anda first end plate manifold component,
combined with the first end structure component, a rigidity of the first
end plate structure component being greater than a rigidity of the first
end plate manifold component, the first end plate manifold component
having at least one first open manifold and at least one first close
manifold, wherein the first open manifold is connected to external;a
second end plate, comprising:a second end plate structure component,
having at least one second through hole; anda second end plate manifold
component, combined with the second end plate structure component, the
first end plate manifold component and the second end plate manifold
component being disposed between the first end plate structure component
and the second end plate structure component, a rigidity of the second
end plate structure component being greater than a rigidity of the second
end plate manifold component, the second end plate manifold component
having at least one second open manifold and at least one second close
manifold, wherein the second open manifold is connected to external;at
least a fuel cell, disposed between the first end plate manifold
component of the first end plate and the second end plate manifold
component of the second end plate, and having a plurality of flow
channels respectively connected to the corresponding first open manifold,
the first close manifold, the second open manifold and the second close
manifold;a first current collector, disposed between the first end plate
manifold component and the at least one fuel cell; anda second current
collector, disposed between the second end plate manifold component and
the at least one fuel cell.

2. The fuel cell stack as claimed in claim 1, wherein a material of the
first end plate structure component or the second end plate structure
component is a metal material.

3. The fuel cell stack as claimed in claim 2, wherein a material of the
first end plate structure component or the second end plate structure
component is selected from a group consisting of ferrous alloy,
non-ferrous alloy, aluminium alloy, titanium alloy and stainless steel.

4. The fuel cell stack as claimed in claim 1, wherein a material of the
first end plate manifold component or the second end plate manifold
component is a polymer material.

5. The fuel cell stack as claimed in claim 4, wherein a material of the
first end plate manifold component or the second end plate manifold
component is selected from a group consisting of rubber, plastics and
fiber composites.

6. The fuel cell stack as claimed in claim 1, wherein the first end plate
manifold component and the second end plate manifold component
respectively have a concave part at a side facing to the at least one
fuel cell, which are respectively used for accommodating the first
current collector and the second current collector, so that the first end
plate manifold component and the first current collector commonly lean
against the at least one fuel cell, and the second end plate manifold
component and the second current collector commonly lean against the at
least one fuel cell.

7. The fuel cell stack as claimed in claim 1, further comprising a
plurality of external pipelines respectively connected to the
corresponding first open manifold and the second open manifold.

8. The fuel cell stack as claimed in claim 7, wherein each of the first
open manifolds and each of the second open manifolds respectively have an
end plane for combining the corresponding external pipeline.

9. The fuel cell stack as claimed in claim 8, further comprising a
plurality of O-rings respectively disposed between the end planes and the
corresponding external pipelines, and each of the end planes having a
ring-shape groove for accommodating the O-ring.

10. The fuel cell stack as claimed in claim 8, wherein each of the
external pipelines has a flange locked on the end plane of the
corresponding first open manifold or the corresponding second open
manifold.

11. The fuel cell stack as claimed in claim 10, further comprising a
plurality of screws locked between the external pipelines and the
corresponding end planes.

12. The fuel cell stack as claimed in claim 1, wherein each of the
external pipelines and the corresponding first open manifold or the
corresponding second open manifold are formed integrally.

13. The fuel cell stack as claimed in claim 1, further comprising at least
one clamping assembly for exerting a clamping load to an outer edge of
the first end plate structure component and an outer edge of the second
end plate structure component, so as to clamp the first end plate
structure component, the first end plate manifold component, the first
current collector, the at least one fuel cell, the second current
collector, the second end plate manifold component and the second end
plate structure component together.

14. The fuel cell stack as claimed in claim 13, wherein the clamping
assembly comprises:a first load component and a second load component,
respectively disposed at the outer edge of the first end plate structure
component and the outer edge of the second end plate structure
component;a connector, penetrating through the first end plate structure
component and the second end plate structure component, and connecting
the first load component and the second load component; andtwo elastic
components, respectively disposed between the first load component and
the first end plate structure component, and between the second load
component and the second end plate structure component.

15. The fuel cell stack as claimed in claim 14, wherein the elastic
components are disk-type springs or compression springs.

16. The fuel cell stack as claimed in claim 14, wherein the outer edge of
the first end plate structure component and the outer edge of the second
end plate structure component respectively have a concave for
accommodating the first load component and the second load component.

17. The fuel cell stack as claimed in claim 14, wherein the first load
component or the second load component comprises:a bottom plate, having a
first supporting surface for supporting the corresponding elastic
component; anda stop block, disposed on the first supporting surface of
the bottom plate, for leaning against the first end plate structure
component or the second end plate structure component when the elastic
component is excessively pressed.

18. The fuel cell stack as claimed in claim 1, wherein the first end plate
structure component has at least one first through hole, the first open
manifold is located in the first through hole and is connected to
external, and the first close manifold extends into the first end plate
structure component.

19. The fuel cell stack as claimed in claim 18, wherein the second end
plate structure component has at least one second through hole, the
second open manifold is located in the second through hole and is
connected to external, and the second close manifold extends into the
second end plate structure component.

20. The fuel cell stack as claimed in claim 1, wherein the first end plate
manifold component has a first concave, and the first end plate structure
component is inlaid to the first concave.

21. The fuel cell stack as claimed in claim 20, wherein the second end
plate manifold component has a second concave, and the second end plate
structure component is inlaid to the second concave.

22. The fuel cell stack as claimed in claim 21, further comprising two
elastic components respectively disposed between the first end plate
manifold component and the first end plate structure component, and
between the second end plate manifold component and the second end plate
structure component.

Description:

CROSS-REFERENCE TO RELATED APPLICATION

[0001]This application claims the priority benefit of Taiwan application
serial no. 97147161, filed on Dec. 4, 2008. The entirety of the
above-mentioned patent application is hereby incorporated by reference
herein and made a part of specification.

BACKGROUND OF THE INVENTION

[0002]1. Field of the Invention

[0003]The present invention relates to a fuel cell stack. More
particularly, the present invention relates to a fuel cell stack having
end plates with a high rigidity and a stable chemical/electrochemical
characteristic.

[0004]2. Description of Related Art

[0005]A proton exchange membrane fuel cell (PEMFC) is also referred to as
a polymer electrolyte membrane fuel cell, and a constitution of a single
fuel cell 100 is as that shown in FIG. 1, in which a central part is a
membrane electrode assembly (MEA) 110, and gas diffusion layers (GDLs)
120 and 130 are disposed at two sides of the MEA 110, and are located
between two bipolar plates 140 and 150. The MEA 110 is consisted of a
proton exchange membrane 111 and catalyst layers 112 and 113 coated at
two sides of the proton exchange membrane 111. After reaction fluid
required by the fuel cell 100 is distributed by flow channels 160 and 170
in the bipolar plates and the GDLs 120 and 130, an electrochemical
reaction is occurred at the catalyst layers 112 and 113. The reaction
fluid required by an anode side of the fuel cell 100 is hydrogen or humid
hydrogen, and when the reaction fluid contacts the catalyst layer 112 of
the MEA 110 at the anode side, an oxidation reaction is occurred:
H2→2H++2e.sup.-. Electrons generated by the oxidation
reaction are conducted by an external circuit, and hydrogen ions can pass
through the proton exchange membrane 111 and get to a cathode side of the
MEA 110, so that with assistance of humid oxygen or humid air at the
cathode side, a reduction reaction:
O2+4H++4e.sup.-→2H2O is occurred on the catalyst
layer 113 of the MEA 110 at the cathode side. It should be noticed that
the proton exchange membrane 111 is a membrane containing water, so that
only the hydrogen ions can pass though the water molecules contained in
the proton exchange membrane 111, and other gas molecules cannot pass
there through.

[0006]According to the above description, it is known that the fuel cell
100 generates power through the electrochemical reaction between the
hydrogen and the oxygen, and a reaction outcome is clean water, which
will not cause pollution to the environment. Since the fuel cell has
advantages of high efficiency and fast response, etc, it is regarded as
one of the alternative energy sources of the future. Moreover, the single
fuel cell 100 can be stacked in serial to form a fuel cell stack as that
shown in FIG. 2, so as to increase an output voltage to meet different
power demands and applications. FIG. 2 is a side view of a conventional
fuel cell stack, in which two end plates 210 and 220 located at two sides
and a plurality of fastening elements 230 are used to tightly stack a
plurality of single fuel cells 100, reaction fluid 261 enters the fuel
cell stack 200 through a reaction fluid inlet manifold 260 and is
uniformly distributed to each of the single fuel cell 100. The electrons
generated by the electrochemical reaction are conducted to external for
utilization through current collectors 240 and 250 located at two sides
of the fuel cell stack 200, and reacted fluid 271 flows outside the fuel
cell stack 200 through a reaction fluid outlet manifold 270. Moreover,
cooling fluid 282 enters the fuel cell stack 200 through a cooling fluid
inlet manifold 280 to maintain a suitable temperature of the fuel cell
stack 200 during operation, and cooled fluid 283 can be smoothly
exhausted from the fuel cell stack 200 through a cooling fluid outlet
manifold 281.

[0007]One of key factors that influences a performance of the fuel cell
stack 200 is a clamping pressure provided by the two end plates 210 and
220 and the fastening elements 230 when the fuel cell stack 200 is
assembled. Referring to FIG. 1 and FIG. 2, when the clamping pressure is
too great, the MEA 110 is deformed or even damaged due to the pressure,
which may cause a decline of a transmission capacity of the hydrogen
ions. When the clamping pressure is inadequate, an interface contact
resistance between the MEA 110 and the bipolar plates 140 and 150 is
increased, which may also cause a decline of the performance of the fuel
cell stack 200. Another factor that influences the performance of the
fuel cell stack 200 is stability of chemical/electrochemical
characteristics of a material of the end plates 210 and 220. The reaction
fluid outlet/inlet manifolds 270 and 260 and the cooling fluid
outlet/inlet manifolds 281 and 280 of the end plates 210 and 220 are
mainly used for guiding the reaction fluid 261 and 271 and the cooling
fluid 282 and 283 with a temperature of 60-80° C. and a relative
humidity of more than 90%, Unstable chemical/electrochemical
characteristics of the material of the end plates 210 and 220 may lead to
corrosion and exfoliation of the manifold surface, and exfoliations can
block the flow channels 160 and 170, and accordingly the MEA 110 is
contaminated and the performance of the fuel cell stack 200 is decreased.

[0008]In summary, the end plates 210 and 220 and the fastening elements
230 are not only required to provide a uniform clamping pressure when the
single fuel cells are assembled, but also the end plates 210 and 220 are
required to have a high rigidity and a stable chemical/electrochemical
characteristic under the operation temperature, humidity and pressure of
the fuel cell stack 200, so as to maintain the performance of the fuel
cell stack 200 and prolong a lifespan of the fuel cell stack 200.

SUMMARY OF THE INVENTION

[0009]The present invention is directed to a fuel cell stack, which can
maintain a stable fuel cell performance.

[0010]The present invention provides a fuel cell stack including a first
end plate, a second end plate, at least a fuel cell, a first current
collector and a second current collector. The first end plate includes a
first end plate structure component and a first end plate manifold
component, wherein the first end plate manifold component is combined
with the first end structure component, and a rigidity of the first end
plate structure component is greater than that of the first end plate
manifold component. The first end plate manifold component has at least
one first open manifold and at least one first close manifold, wherein
the first open manifold is connected to external. The second end plate
includes a second end plate structure component and a second end plate
manifold component, wherein the second end plate structure component has
at least one second through hole, and the second end plate manifold
component is combined with the second end plate structure component. The
first end plate manifold component and the second end plate manifold
component are disposed between the first end plate structure component
and the second end plate structure component, and a rigidity of the
second end plate structure component is greater than that of the second
end plate manifold component. The second end plate manifold component has
at least one second open manifold and at least one second close manifold,
wherein the second open manifold is connected to external. The at least
one fuel cell is disposed between the first end plate manifold component
and the second end plate manifold component, and the at least one fuel
cell has a plurality of flow channels respectively connected to the
corresponding first open manifold, the first close manifold, the second
open manifold and the second close manifold. The first current collector
is disposed between the first end plate manifold component and the at
least one fuel cell. The second current collector is disposed between the
second end plate manifold component and the at least one fuel cell.

[0011]In the present invention, two or more materials are used to form
composite end plates, which can maintain a high rigidity and a stable
chemical/electrochemical characteristic under an operation temperature,
humidity and pressure of the fuel cell stack. Moreover, the composite end
plates having characteristics of good corrosion resistance, electrical
insulation, low heat conduction loss and light-weight, etc. can be
designed according to different material characteristics, so as to
maintain and improve the performance of the fuel cell stack.

[0012]In order to make the aforementioned and other features and
advantages of the present invention comprehensible, several exemplary
embodiments accompanied with figures are described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]The accompanying drawings are included to provide a further
understanding of the invention, and are incorporated in and constitute a
part of this specification. The drawings illustrate embodiments of the
invention and, together with the description, serve to explain the
principles of the invention.

[0014]FIG. 1 is a schematic diagram illustrating a structure of a single
fuel cell.

[0015]FIG. 2 is a side view of a conventional fuel cell stack.

[0016]FIG. 3 is a three-dimensional view of a fuel cell stack according to
an embodiment of the present invention.

[0017]FIG. 4 is a three-dimensional view of end plates of a fuel cell
stack according to an embodiment of the present invention.

[0018]FIG. 5 is a cross-sectional view of end plates of FIG. 4 along a
plane A1A2/B1B2.

[0019]FIG. 6 is an exploded view of end plates of fuel cells and a
compression assembly mechanism according to an embodiment of the present
invention.

[0020]FIG. 7 is a three-dimensional view of an external pipeline according
to an embodiment of the present invention.

[0021]FIG. 8 is a three-dimensional view of a load component according to
an embodiment of the present invention.

[0022]FIG. 9 is a three-dimensional view of end plates of fuel cells and a
compression assembly mechanism according to an embodiment of the present
invention.

[0023]FIG. 10 is a cross-sectional view of end plates of fuel cells and a
compression assembly mechanism of FIG. 9 along a plane C1C2.

[0024]FIG. 11 is a cross-sectional view of end plates of fuel cells along
a plane A1A2/B1B2 plane according to another embodiment of the present
invention.

[0025]FIG. 12 is a cross-sectional view of end plates of fuel cells along
a plane A1A2/B1B2 according to still another embodiment of the present
invention.

DESCRIPTION OF THE EMBODIMENTS

[0026]FIG. 3 is a three-dimensional view of a fuel cell stack according to
an embodiment of the present invention. FIG. 4 is a three-dimensional
view of end plates of the fuel cell stack according to an embodiment of
the present invention, in which a first end plate 310 is represented by a
comprehensive diagram, and a second end plate 320 is represented by an
exploded diagram. FIG. 5 is a cross-sectional view of the end plates of
FIG. 4 along a plane A1A2/B1B2. Referring to FIG. 3, FIG. 4 and FIG. 5,
the first end plate 310 includes a first end plate structure component
311 and a first end plate manifold component 312, wherein the first end
structure component 311 is combined with the first end plate manifold
component 312, and a rigidity of the first end plate structure component
311 is greater than that of the first end plate manifold component 312.
The first end plate manifold component 312 has at least one first open
manifold 313 and at least one first close manifold 314, wherein the first
open manifold 313 is connected to external for leading reaction fluid or
cooling fluid required during the operation of the fuel cells.

[0027]The second end plate 320 includes a second end plate structure
component 321 and a second end plate manifold component 322, wherein the
second end plate structure component 321 has at least one second through
hole 325, and the second end plate structure component 321 is combined
with the second end plate manifold component 322, and a rigidity of the
second end plate structure component 321 is greater than that of the
second end plate manifold component 322. The first end plate manifold
component 312 and the second end plate manifold component 322 are
disposed between the first end plate structure component 311 and the
second end plate structure component 321. The second end plate manifold
component 322 has at least one second open manifold 323 and at least one
second close manifold 324, wherein the second open manifold 323 is
connected to external for leading the reaction fluid or the cooling fluid
required during the operation of the fuel cells.

[0028]The fuel cell stack 300 of the present embodiment includes at least
one fuel cell 330, a first current collector 340 and a second current
collector 350. A quantity of the fuel cells 330 is not limited by the
present invention, and in the present embodiment, a plurality of stacked
fuel cells 330 is illustrated for description. The stacked fuel cells 330
are disposed between the first end plate manifold component 312 and the
second end plate manifold component 322, and the fuel cells 330 has a
plurality of flow channels respectively connected to the corresponding
first open manifold 313, the first close manifold 314, the second open
manifold 323 and the second close manifold 324, so that the reaction
fluid or the cooling fluid came from the external of the fuel cell stack
300 can be uniformly distributed to each of the fuel cells 330. The first
current collector 340 is disposed between the first end plate manifold
component 312 and the fuel cells 330, and the second current collector
350 is disposed between the second end plate manifold component 322 and
the fuel cells 330. The first current collector 340 and the second
current collector 350 can conduct electrons generated by an
electrochemical reaction of the reaction fluid to the external of the
fuel cell stack 300 for utilization.

[0029]Moreover, a material of the first end plate structure component 311
or the second end plate structure component 321 can be metal, for
example, one of a group consisting of ferrous alloy, non-ferrous alloy,
aluminium alloy, titanium alloy and stainless steel, which can provide a
high mechanical rigidity required by the first end plate 310 and the
second end plate 320. Since the first end plate manifold component 312
and the second end plate manifold component 322 directly contact the
current collectors 340 and 350 and the reaction fluid or the cooling
fluid, a material thereof is preferably a polymer material with features
of stable chemical/electrochemical characteristic, good electrical
insulation property, low heat loss, and good corrosion resistance, such
as one of a group consisting of rubber, plastics and fiber composites.

[0030]FIG. 6 is an exploded view of the end plates of the fuel cells and a
compression assembly mechanism according to an embodiment of the present
invention. FIG. 7 is a three-dimensional view of an external pipeline 360
of the end plates according to an embodiment of the present invention.
Referring to FIG. 6 and FIG. 7, the fuel cell stack 300 has a plurality
of external pipelines 360 respectively connected to the corresponding
first open manifolds 313 and the second open manifolds 323, wherein each
of the first open manifolds 313 and each of the second open manifolds 323
respectively have an end plane 313a and an end plane 323a, which are used
for combining with the corresponding external pipeline 360. The end
planes 313a and 323a respectively has a ring-shape groove 313b and a
ring-shape groove 323b, which are used for accommodating a plurality of
O-rings 370 disposed between the end planes 313a and 323a and the
external pipelines 360, so as to provide a good gastight effect.
Moreover, each of the external pipelines 360 has a flange 361. In the
present embodiment, the flange 361 has at least one arc hole, so that a
plurality of screws 380 can be locked between the external pipeline 360
and the corresponding end planes 313a and 323a, and the external pipeline
360 can be rotated to facilitate combining the external pipelines.

[0031]The fuel cell stack 300 of the present embodiment includes at least
one clamping assembly 390, which is used for exerting a clamping load to
an outer edge of the first end plate structure component 311 and an outer
edge of the second end plate structure component 321, so as to
sequentially clamp the first end plate structure component 311, the first
end plate manifold component 312, the first current collector 340, the at
least one fuel cell 330, the second current collector 350, the second end
plate manifold component 322 and the second end plate structure component
321. The clamping assembly 390 includes a first load component 391, a
second load component 392, a connector 393 and two elastic components
394, wherein the first load component 391 and the second load component
392 are respectively disposed at the outer edge of the first end plate
structure component 311 and the outer edge of the second end plate
structure component 321; the connector 393 penetrates through the first
end plate structure component 311 and the second end plate structure
component 321 and connects the first load component 391 and the second
load component 392; while the elastic components 394 are respectively
disposed between the first load component 391 and the first end plate
structure component 311, and between the second load component 392 and
the second end plate structure component 321. The elastic component 394
can be a compressible component, for example, a disk-type spring or a
compression spring, which is used for sustaining the clamping load.

[0032]The first end plate manifold component 312 and the second end plate
manifold component 322 respectively have concave parts 316 and 326 at a
side facing to the fuel cell 330, which are respectively used for
accommodating the first current collector 340 and the second current
collector 350 during assembling, so that the first end plate manifold
component 312 and the first current collector 340 can commonly lean
against one side of the fuel cell 330, and the second end plate manifold
component 322 and the second current collector 350 can commonly lean
against another side of the fuel cell 330. Moreover, the outer edge of
the first end plate structure component 311 and the outer edge of the
second end plate structure component 321 respectively have concaves 317
and 327, which are respectively used for accommodating the first load
component 391 and the second load component 392 during the assembling.

[0033]FIG. 8 is a three-dimensional view of a load component according to
an embodiment of the present invention. As shown in FIG. 8, the load
component 391 or 392 has a bottom plate 391a and a stop block 391b,
wherein the bottom plate 391a has a first supporting surface 391c, which
is used for supporting the corresponding elastic component 394, and
sustaining a reacting force generated when the elastic component 394 is
compressed. The stop block 391b is disposed on the first supporting
surface 391c, which is used for leaning against the first end plate
structure component 311 or the second end plate structure component 321
when the elastic component 394 is excessively pressed, so as to protect
the elastic component 394, and avoid damage of the elastic component 394
caused by improper assembling pressure. The step block 391b can include
an inner thread hole, which is used for locking the connector 393 during
the assembling.

[0034]In addition, the first end plate 310 of the fuel cell stack 300 is
formed by combining the first end plate structure component 311 and the
first end plate manifold component 312. The first end plate structure
component 311 has at least one first through hole 315. When the fuel
cells are assembled, the first open manifold 313 is disposed in the
corresponding first through hole 315 for connecting to the external, and
can be combined with the external pipeline 360. The first close manifold
314 extends into the first end plate structure component 311 to form a
circumfluence chamber, so that the reaction fluid can be uniformly
distributed to each of the fuel cells. The second end plate structure
component 321 and the second end plate manifold component 322 are
assembled in a same approach. The second open manifold 323 is disposed in
the corresponding second through hole 325 for connecting to the external,
and the second close manifold 324 extends into the second end plate
structure component 321 to form the circumfluence chamber. In the present
embodiment, according to different material characteristics of the
components that form the first end plate 310 and the second end plate
320, by suitably selecting and combining the materials, the first end
plate 310 and the second end plate 320 may simultaneously have the
advantages of high mechanical rigidity, electrical insulation, and stable
chemical/electrochemical characteristic. Besides combining the two types
of the components to form the first end plate 310 and the second end
plate 320, a layer of heat-insulating material can further be added
during the assembling, so that the first end plate 310 and the second end
plate 320 may have a heat preservation function. Accordingly, a heat
conduction loss is reduced, an operation temperature of the fuel cells is
maintained and a performance of the fuel cells is stabilized. FIG. 9 is a
three-dimensional view of the end plates of the fuel cells and a
compression assembly mechanism according to an embodiment of the present
invention. FIG. 10 is a cross-sectional view of FIG. 9 along a plane
C1C2.

[0035]FIG. 11 is a cross-sectional view of the end plates of the fuel
cells along the plane A1A2/B1B2 according to another embodiment of the
present invention. The external pipelines 360 are not combined to the
first and the second end plate manifold components 312 and 322 through a
locking approach, but are formed integrally with the corresponding first
open manifold 313 or the second open manifold 323, so as to avoid a
follow-up locking procedure during the assembling. Moreover, a gas
leakage problem between the external pipeline 360 and the first and the
second end plate manifold components 312 and 322 can be avoided, which
may facilitate the assembling and utilization.

[0036]FIG. 12 is a cross-sectional view of the end plates of the fuel
cells along the plane A1A2/B1B2 according to still another embodiment of
the present invention. In the present embodiment, the first end plate
manifold component 312 and the second end plate manifold component 322
respectively a first concave 318 and a second concave 328, and the first
end plate structure component 311 and the second end plate structure
component 321 are respectively inlaid to the first concave 318 and the
second concave 328. In coordination with such assembling method and the
elastic components 318a and 328a disposed between the first and the
second end plate manifold components 312 and 322 and the first and the
second end plate structure components 311 and 321, delivery of integral
clamping pressure is achieved.

[0037]In summary, by selecting the materials of the end plate structure
components and the end plate manifold components, composite end plates
having advantages of high rigidity, good corrosion resistance, electrical
insulation, stable chemical/electrochemical characteristic and
light-weight, etc. are formed. Moreover, a layer of heat-insulating
material can further be added to the end plate to reduce a heat
conduction loss during the operation of the fuel cells, so as to maintain
a stable performance of the fuel cells, and improve a durability of the
fuel cells. The assembling mechanism of the present invention can
provides a suitable and uniform clamping pressure, so as to reduce an
interface contact resistance of the fuel cells, and improve the
performance of the fuel cells. Moreover, the components of the present
invention have simple designs, so that a fabrication cost of the
components can be reduced through a mass production. In addition, the
components are easy to be assembled, and are suitable for designs of all
types of the fuel cell stacks, which are convenient for applications.

[0038]It will be apparent to those skilled in the art that various
modifications and variations can be made to the structure of the present
invention without departing from the scope or spirit of the invention. In
view of the foregoing, it is intended that the present invention cover
modifications and variations of this invention provided they fall within
the scope of the following claims and their equivalents.